Multiple pump



M 29 19 E. A. JOHNSON MULTIPLE PUMP 2 Sheets-Sheet 1 Filed Jan. 7, 1957 a G F INVENTOR. EL DON A. JOHNSON ATTORNEY May 29, 1962 JOHNSON 3,036,524

MULTIPLE PUMP Filed Jan. 7, 1957 2 Sheets-Sheet 2 M IIIIIIIIIIIIIIIIIII'II A i G A 981 \m F I c. 3.

EIIMIIMI INVENTOR. ELDON A. JOHNSON ATTORNEY 3,036,524 MULTKPLE PUMP Eldon A. Johnson, St. Louis, Mo., assignor to ACE industries, Incorporated, New York, N.Y., a corporation of New Jersey Filed Jan. 7, 1957, Ser. No. 632,687 7 Claims. (Cl. 103-4) This invention relates to pumps and more particularly to a multiple pump arrangement comprising two reciprocating pumps coacting to discharge fluids under constant pressure and variable volume.

An object of the invention resides in the provision of a variable-delivery, constant pressure pump embodying two pumping elements alternately operable during each operating cycle to pump gases and/ or liquids to thus provide a more uniform output flow and greater volume with less movement of the pumping elements, thereby reducing wear of parts and increasing the service life of the pump.

Another object of the invention resides in the provision of a multiple pump arrangement in which one of the pumps becomes inactive when the fluid output reaches a predetermined maximum pressure.

A further object of the invention resides in the provision of a multiple pump arrangement in which at least one of the pumping elements is actuated by spring means on its discharge stroke,

Another object of the invention is to provide a multiple pump arrangement in which each pumping element is actuated on its discharge stroke by its respective spring means.

The invention embodies other novel features, details of construction, and arrangement of parts which are hereinafter set forth in the specification and claims and illustrated in the accompanying drawings, wherein:

FIG. 1 is a vertical sectional view illustrating a pump embodying my features of the invention.

FIG. 2 is a transverse sectional view taken along the line 22 of FIG. 1.

FIG. 3 is a vertical sectional view illustrating a modified form of the invention.

FIG. 4 is a vertical sectional view taken along the line 44 of FIG. 3.

FIG. 5 is a transverse sectional view taken along the line 5-5 of FIG. 3.

Referring now to the drawings for a better understanding of the invention and more particularly to FIGS. 1 and 2 therein, the pump is shown as comprising a rocker arm 6 pivotally mounted intermediate its ends on a pin '7 fixed on a primary spring housing 8, one end of the arm being urged into functional engagement against a rotary cam 9 by means of a compression spring 11, and the other end of the arm being bifurcated to straddle the shank of a primary actuating rod 12 secured to a flexible primary pumping diaphragm 13.

The primary pumping diaphragm 13 has its marginal portion clamped between the spring housing 8 and a primary valve housing 14- and has its central portion clamped between plates 16 and 17. A resilient sealing ring 18 is provided with a central aperture to snugly receive the shank of the actuating rod 12 and has its marginal portion tightly engaged against an annular seat 19 by means of a compression spring 21 provided to engage and actuate the diaphragm 13 on its discharge stroke. The bifurcated end of the rocker arm 6 is engaged under a head 22 on the actuating rod 12 to compress the spring 21 during the intake stroke of the diaphragm 13.

The primary valve housing 14 is provided with inlet ports 23 and outlet ports 24 normally closed by springpressed inlet and outlet check valves 26 and 27, respec- 3,036,524 Patented May 29, 1962 tively. A secondary valve housing 28 is secured to the housing 14 and provided with inlet ports 29 and outlet ports 31 normally closed by spring-pressed inlet and outlet check valves 32 and 33, respectively. The housings 14 and 28 define inlet and outlet chambers 34 and 36 communicating with inlet and outlet passages 37 and 38, respectively.

The housings 14 and 28 are formed with coaxial bores to slidably receive a secondary actuating rod 39 having one end thereof secured to a flexible secondary pumping diaphragm 41 and its other end engageable by the primary actuating rod 12. The marginal portion of the diaphragm i1 is clamped between the valve housing 28 and an end housing 42 and has its central portion clamped between plates 43 and 44. The end housing 42 is formed with a spring chamber 46 to receive a relatively light compression spring 47 engageable against the diaphragm 41. The housings 8 and 42 are formed with vents 47a and 48 leading from their respective spring chamber to atmosphere. The several housings and diaphragms are adapted to be secured in assembled relationship by means of screws or bolts 49 extending therethrough.

While the pump structure thus shown and described is adapted for use in pumping various liquids and gases, it is particularly suitable for use in supplying variable quantities of liquid fuel under constant pressure from a fuel tank to a conventional constant level carburetor of an internal combustion engine. During the pumping of liquid fuel, the cam 9 acts through the rocker arm 6 to move the rod 12 and diaphragm 13 upwardly to compress the spring 21 and to draw fuel from the intake chamber 34 past the inlet check valve 26 into the primary pump chamber 51. The spring 21 then acts to move the diaphragm 13 in the opposite direction to force the fuel from the pump chamber 51 past the outlet check valve 27 into and rough the outlet chamber 36 and passage 38 and thence past a conventional float controlled needle valve of a carburetor.

When the fuel being supplied to the carburetor is in a solid liquid condition, free of gases or vapors, the auxiliary diaphragm 41 is inactive due to maximum pressures produced by the primary diaphragm 13 against a closed or partially closed needle valve.

In the event the fuel contains vapors or gas bubbles, the relatively strong spring 21 acts through the pirmary diaphragm 13 to move the secondary diaphragm 41 to compress the relatively weak spring 47 and draw fuel and vapors past the inlet check valve 32 into the secondary pump chamber 52. When the primary diaphragm 13 is retracted by the cam and rocker arm, the compressed spring 47 acts against the secondary diaphragm 41 to force the fuel and vapors from the pump chamber 52 past the outlet check valve 33 into the outlet chamber 36 and thence to the carburetor.

The secondary pump thus coacts with the primary pump to serve as a fuel and vapor pump to prevent or relieve a vapor lock condition in the fuel system due to high ambient temperatures and heat radiated from an engine. The primary and secondary pumps each have a discharge stroke during each revolution of the cam.

FIGS. 3, 4, and 5 illustrate a modified form of the invention in which the primary and second diaphragrns 13 and 41 are interconnected by a rod 53 movable in one direction by the rocker arm 6 and in the other direction by the compression spring 21. In this form of the invention, it will be noted that the primary diaphragm has a positive intake stroke and a spring discharge stroke, while the secondary diaphragm 41 has a spring intake stroke and a positive discharge stroke.

To provide a constant maximum discharge pressure, the pump chambers 5.1 and 52 are provided with pressure relief valves 55 and 54, respectively, leading to the intake 3 chamber 34. This form of the invention is otherwise the same as the form heretofore described, and similar numbers have been applied to corresponding parts.

While the invention has been shown in but two forms, it is obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications Without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. In a multiple pump arrangement, primary and secondary valve housings providing fluid inlet and outlet chambers having inlet and outlet passages, respectively, flexible primary and secondary diaphragms defining with their respective valve housings primary and secondary pump chambers, inlet and outlet ports leading from said inlet and outlet chambers, respectively, to their respective pump chambers, check valves for said ports, means to move said diaphragms, spring housings secured to their respective valve housings, said means including a compression spring in each spring housing to engage and move its respective diaphragm during its discharge stroke, and a rocker arm to move said primary diaphragm only during its intake stroke, said secondary diaphragm being movable on its intake stroke by the compression spring associated 'with said primary diaphragm, primary and secondary actuating rods secured to their respective diaphragms for abutting engagement, said rocker arm being engageable with said primary actuating rod.

2. In a multiple pump arrangement, primary and secondary valve housings providing fluid inlet and outlet chambers having inlet and outlet passages, respectively, flexible primary and secondary diaphragms defining with their respective valve housings primary and secondary pump chambers, inlet and outlet ports leading from said inlet and outlet chambers, respectively, to their respective pump chambers, check valves for said ports, means to move said diaphragms, spring housings secured to their respective valve housings, said means including a compression spring in each spring housing to engage and move its respective diaphragm during its discharge stroke, and a rocker arm to move said primary diaphragm only during its intake stroke, said secondary diaphragm being movable on its intake stroke by the compression spring associated with said primary diaphragm, primary and secondary actuating rods secured to their respective diaphragms for abutting engagement, said rocker arm being engageable with said primary actuating rod, said primary spring having a greater load capacity than said secondary spring to compress the latter during the intake stroke of the secondary diaphragm.

3. A multiple fuel pump for an engine comprising a housing, a pair of spaced diaphragms sealed at the peripheries thereof Within said housing and positioned on a common axis in parallel planes, said housing having an inlet chamber with an inlet thereto and an outlet chamber with an outlet therefrom between said spaced diaphragms, one of said diaphragms forming a first pumping chamber with said housing, the other one of said diaphragms forming a second pumping chamber with said housing, said housing having a plurality of ports extending between said inlet and outlet chambers and said first and scond pumping chambers, valve means within said housing for controlling fuel flow through said ports, a pair of rods aligned on said common axis within said housing and with adjacent ends thereof in abutment, a first one of said pair of rods fixed to said one diaphragm and the second one of said pair of rods fixed to said other one of said diaphragms, and means to reciprocate said diaphragms, said last means including structure connected to said first one of said rods for moving said one diaphragm in only one direction and a spring connected between said housing and said one diaphragm for moving said one diaphragm and said rods in an opposite direction only.

4. A multiple fuel pump for an engine comprising a housing, a pair of spaced diaphragms sealed at the peripheries thereof within said housing and positioned on a common axis in parallel planes, said housing having an inlet chamber with an inlet thereto and an outlet chamber with an outlet therefrom between said spaced diaphragms, one of said diaphragms forming a first pumping chamber with said housing, the other one of said diaphragms forming a second pumping chamber with said housing, said housing having a plurality of ports extending between said inlet and outlet chambers and said first and second pumping chambers, valve means within said housing for controlling fuel flow through said ports, a first rod and a second rod aligned on said common axis within said housing and with adjacent ends thereof in abutment, said first rod fixed to said one diaphragm and said second rod fixed to said other one of said diaphragms, said adjacent end of said second rod operatively extending into said first pumping chamber whereby a predetermined fluid pressure Within said first pumping chamber will maintain the other of said two diaphragms in an inoperative position, and means to reciprocate said diaphragms, said last means including a lost-motion connection connected to said first one of said rods for moving said one diaphragm in only one direction and a spring connected between said housing and said one diaphragm for moving said one diaphragm and said rods in an opposite direction only.

5. A multiple fuel pump for an engine comprising a housing, a pair of spaced diaphragms sealed at the peripheries thereof within said housing and positioned on a common axis in parallel planes, said housing having an inlet chamber With an inlet thereto and an outlet chamber with an outlet therefrom between said spaced diaphragms, one of said diaphragms forming a first pumping chamber with said housing, the other one of said diaphragms forming a second pumping chamber with said housing, said housing having a plurality of ports extending between said inlet and outlet chambers and said first and second pumping chambers, valve means within said housing for controlling fuel flow through said ports, a first rod and a second rod aligned on said common axis within said housing and with adjacent ends thereof in abutment, said first rod fixed to said one diaphragm and said second rod fixed to said other one of said diaphragms, and means reciprocating said diaphragms, said last means including a lost-motion connection connected to said first one of said rods for moving said one diaphragm in only one direction, a first spring connected to said one diaphragm for moving said one diaphragm and said rods in an opposite direction only and a second spring connected to said other one of said diaphragms to move said other diaphragm in said one direction only.

6. A multiple fuel pump for an engine comprising a housing, a pair of spaced diaphragms sealed at the peripheries thereof within said housing, actuating rod means connected to said diaphragms, said housing having an inlet chamber with an inlet thereto and an outlet chamber with an outlet therefrom between said spaced diaphragms, one of said diaphragms forming a primary pumping chamber with said housing, the other one of said diaphragms forming a secondary pumping chamber with said housing, said housing having a plurality of ports extending between said inlet and outlet chambers and said primary and secondary pumping chambers, valve means within said housing for controlling fuel flow through said ports, and means to reciprocate said diaphragms, said last means including structure connected to said actuating rod means for moving said one diaphragm in one direction only, and a spring connected to said actuating rod means for moving said diaphragms in an opposite direction only, said actuating rod means including a first and a second rod mounted within said housing with said first rod fixed to said one diaphragm and said second rod fixed to said other one of said diaphragms, one end of said second rod operatively extending into said primary pumping chamber whereby a predetermined fluid pressure within said primary pumping chamber will maintain said other one of said diaphragms inoperative.

7. A multiple fuel pump for an engine comprising a housing, a pair of spaced diaphragms sealed at the peripheries thereof within said housing, said housing having an inlet chamber With an inlet opening and an outlet chamber with an outlet opening between said spaced diaphragms, one of said diaphragms forming a primary pumping chamber with said housing, the other one of said diaphragms forming a secondary pumping chamber 'With said housing, said housing having a plurality of ports extending between said inlet and outlet chambers and said primary and secondary pumping chambers, valve means within said housing for controlling fuel flow through said ports, a first and a second rod mounted in alignment within said housing with said first rod fixed to said one diaphragm and said second rod fixed to said other one of said diaphragms, means connected to said first rod for moving said one diaphragm in one direction only, a first spring between said housing and said one diaphragm for moving said diaphragms in an opposite direction only, one end of said second rod operatively extending into said primary pumping chamber whereby a predetermined fluid pressure within said primary pumping chamber will maintain said other one of said diaphragms in an operative position, and a second spring biasing said second rod into abutting engagement with said first rod.

References Cited in the file of this patent UNITED STATES PATENTS 12,284 Roberts Jan. 23, 1855 207,784 Watson Sept. 3, 1878 862,867 Eggleston Aug. 6, 1907 1,804,524 Brown May 12, 1931 2,036,452 Babitch et a1. Apr. 7, 1936 2,139,571 Avigdor Dec. 6, 1938 2,151,043 Paton Mar. 21, 1939 2,344,287 Creveling Mar. 14, 1944 2,381,259 Cofiey Aug. 7, 1945 2,621,594 Katcher Dec. 16, 1952 2,819,588 Sarto Ian. 14, 1958 FOREIGN PATENTS 349,474 Great Britain May 11, 1931 

